Dry chemical fire extinguisher valve



July 2, 1957 l. NURKIEWICZ DRY CHEMICALFIRE EXTINGUISHER VALVE FiledApril 20, 1954 INVENTOIR.

164 4701; )Vuz/msW/cz ATTORNEY Patented July 2, 1957 DRY CHEMICAL FIREEXTINGUISHER VALVE Ignatius Nurkiewicz, Brooklyn, N. Y., assignor toStop- Fire, Inc., Brooklyn, N. Y., a corporation of New York ApplicationApril 20, 1954, Serial No. 425,017

2 Claims. (Cl. 137-4431) This invention relates to a dry chemical fireextinguisher valve.

This application is a continuation-in-part of an application filed byapplicant on July 15, 1953, Serial Number 368,131, now abandoned.

An effective type of fire extinguishers employs a fine dry powder, suchas a carbonate of soda, which is propelled onto a fire by compressedgas. Ordinarily, the powder is carried in a container in which the gasis held under heavy pressure. The outlet tube has its intake endsubmerged in the powder so that when the discharge valve is opened astream of gas issues from the device, carrying with it the extinguishingpowder.

In such a fire extinguisher, the gas and powder are usually under thecontrol of a hand operated valve, and normally only enough of the chargeis released to put out the fire. Difficulty is experienced, however,with the present valves in that when the valve is closed again, afterthe initial discharge, the valves may not seat themselves tight enoughto prevent leakage of the gas pressure. Even a very slow leakage, duringa long period of non-use, may make the device inoperative, when the nextemergency arises, for lack of gas pressure.

Such extinguishers are provided with a pressure gage, which willnormally be examined after each interval of use. If the pressure is toolow, the extinguisher will be refilled before it is hung up. It is,however, an object of this invention to insure that after a period oflong disuse that the extinguisher will still retain the degree ofpressure it had when it was last used or inspected. That is, it is anobject of this invention, to provide a valve which will completely sealthe extinguisher, after every operation.

The principal cause of the failure of the present valves to reseal theclosure, is the adhesion of small grains of the powder to theco-operating parts, so that the valve and the valve seat may be heldapart by them.

Experiments indicate that there are several factors contributing to thisend. One of which is that Where the powder laden gas stream is caused tomake sudden changes in direction, as it passes through the valve, theimpingement of the particles upon each other, or on the parts of thedevice, causes them to become electrostatically charged, to such anextent that they are attracted to the valve elements.

Moreover, as the air streams change direction, eddies are formed in thegas stream which facilitates the particles falling out of the stream anddepositing on adjacent surfaces.

It is an object of this invention to provide a valve in which the powderparticles do not collect on the valve parts, so that the valve may berepeatedly opened and closed and in which each closing will provide ahermetically tight closure.

It is a further object to provide a device of the character described,in which the valve comes to its seat with a rotary motion, therebyassisting in dislodging any powder that might be stuck to either part,as they come in contact.

The invention accordingly comprises the device hereinafter described,and which is shown in the accompanying drawings, in which Fig. 1 is acentral longitudinal section through the device and Fig. 2 is afragmentary view on the line IIII of Fig. 1.

In the drawings, the numeral 10 represents a valve body provided at itsbottom with suitable connections for attachment to the body of the fireextinguisher container, including the usual syphon tube connecting thebody with the lower portion of the container below the powder level, inthe usual manner.

As shown, the bottom of the body has a bore 13 into which there isfitted a washer 14 comprising a valve seat of anti-friction material.The bore 13 communicates through the Washer with a smaller diameter bore16, thereby providing a shoulder 17 against which the washer 14 istightly pressed. The bore 16 communicates with a discharge opening 18,adapted to be connected with a discharge tube, not shown.

Coaxial with bores 13 and 16 is another bore 20 separated from the bore16 by an annular flange 21 in which there slides a valve stem 22 whichextends upwardly to screw into a hollow stud 23, sliding in bore 20, andwhich carries at its lower end a valve head, or ball, 26.

The essential feature of this invention centers around the cooperationof the ball 26 and the washer 14 and the surrounding parts, and meansfor preventing the entrapping of powder between them and the dislodgingof powder that might otherwise interfere. These parts are so designedthat the powder-laden gas stream, moving upwardly in the bore 13, maymove past the valve head 26 into the bore 16 with a minimum of change indirection, and in such a manner that the gas stream moves as nearlyparallel to the valve surface as it is practical to make it, so that thetendency is to sweep those surfaces clean of dust without depositing anyupon it. The under surfaces of Washer 14 is a truncated cone of suchsize and pitch that the surface of the ball will be substantiallytangent to the cone surface at the inner edge of the Washer. In thisway, the gas stream, at the point of greatest constriction, flows withthe minimum of turbulence. And, moreover, it is led to that point ofconstriction by a gradually converging pathway and it moves from thatconstriction point into an expanding passage. The angle of the elementsof the cone is here shown at substantially 45.

The ball 26 is preferably made of chrome plated brass to resistcorrosion and abrasion, While the washer is made of a resistant plastic,such as Kel F, or nylon, or, preferably, Teflon, which possesses a verylow-coeificient of friction.

The washer, itself, is replaceable. To this end it is threaded to screwinto the bore 13 until it is tight against the shoulder 17. It isconvenient to screw the washer into place as a flat washer, having aslot in the lower face, so that it may be secured into place by a screwdriver, and then to bore out the exposed end of the washer to coneshape, after it is in place. If, in any way, the washer becomes worn, itmay be screwed out, or cut out, and a new washer inserted and bored, asdescribed.

The operating mechanism for the device is designed to give to the ball26 a slight rotation during its vertical movement. This rotation is forthe purpose of dislodging any minute powder grains that otherwise stickto the surface, and to dislodge them While they are being swept away bythe gas stream, as it washes over the valve surface just before thevalve closes. This action, for the purpose of this invention, must bedone simultaneously with the end of the closing action. If done beforethat time the gases may deposit more powder. The move' ment must,therefore, be an automatic portion of the closing movement.

The construction here shown, to accomplish this purpose is as follows:Handle 24 is pivoted at 27 to a bracket 10a upon the body 10. Thishandle is slotted at 28 to pass over the upper end of the stem 22 inposition to engage the upper face of the stud 23. The engagement of thehandle 24 with the stud 23, however, is on one side only of the stud andof that plane containing the axis of the stern which is transverse tothe pivot of the handie. This is accomplished by providing a rib 34 onthe under side of the handle on one side only of the stud. As shown inFig. 1, the rib 34 is at the back side of the stud and in Fig. 2 it ison the left hand side.

The engagement between the rib 34 and the stud 23 is, moreover, abovethe level of the pivot 27 so that as the handle is depressed it gives alateral component to the motion, and with it the valve stem and ball arethus slightly rotated whenever the lever is depressed or released.

With this construction, it will be clear that as the valve is closed themaximum velocity of the jet will be at the inner edge of the conicalsurface of the washer 14, thereby creating the maximum tendency toprevent the collection of powder upon the surfaces. At the same time,however, any powder which might tend to adhere to the valve due toelectrostatic attraction or otherwise, will be rubbed off by the rotarymotion of the valve as it closes, and is blown away.

What I claim:

1. A valve for gas-borne powders comprising a valve body having avertical bore therein, and having an inlet in its lower end and anoutlet at its upper end, a valve stem extending thru said boreterminating at its inlet end in a valve head, said body having a valveseat above said head in position to be engaged thereby, a spring formoving said valve in a direction to engage said valve seat, and handcontrolled mechanism for engaging said stem to move said head away fromsaid valve seat comprising a lever pivoted to said body, said valve stemextending upwardly and engaging said lever at a point above the pivot ofsaid lever, the engagement between said lever and valve stem being onone side only of the center plane of said lever and of said valve stem,whereby the horizontal components of the motion of the lever about 4 itspivot will rotate the valve stem slightly as it is depressed and as itis raised.

2. A valve for gas-borne powders comprising a valve body having avertical bore therein, and having an inlet in its lower end and anoutlet at its upper end, a valve stem extending thru said boreterminating at its inlet end in a ball, said body having a washerproviding a frustro-conical valve seat above said ball in position to beengaged thereby, at its inner edge, a spring for moving said stem in adirection to engage said ball and seat, and hand control mechanism forengaging said stem to move said ball away from said seat comprising alever pivoted to said body, said valve stem extending upwardly andhaving thereon a head engaging said lever at a point above the pivot ofsaid lever, the engagement between said lever and valve stem being onone side only of the center plane of said lever and of said valve stem,whereby the horizontal components of the motion of the lever about itspivot will rotate the valve stem slightly as it is depressed and as itis raised.

References Cited in the file of this patent UNITED STATES PATENTS 54,722Henke May 15, 1866 246,618 Langley Sept. 6, 1881 979,384 Davis Dec. 20,1910 1,142,145 Collar June 8, 1915 1,516,367 Williams Nov. 18, 19241,608,379 Ewald Nov. 23, 1926 1,805,158 Bacon May 12, 1931 2,121,774 HamJune 28, 1938 2,250,220 Cloutier July 22, 1941 2,285,010 Bullock June 2,1942 2,506,074 Fawkes May 2, 1950 2,644,313 Griggs July 7, 19532,646,246 Tucci July 21, 1953 2,661,019 Snyder Dec. 1, 1953 2,701,119Smith Feb. 1, 1955 FOREIGN PATENTS 369,916 Italy Apr. 3, 1939 110,425Australia of 1940 235,825 Switzerland Apr. 16, 1945 907,117 France of1946 815,285 Germany Oct. 1, 1951

